The present invention relates to ceiling fans, and more specifically, to a motor rotor and outer shell mounting structure for ceiling fan, which enables the rotor to be quickly and accurately positioned in the outer shell.
A regular ceiling fan motor, as shown in FIG. 1, is generally comprised of an outer shell C, a stator B, and a rotor A. The outer shell C is comprised of a top cover shell and a bottom cover shell. The top cover shell and bottom cover shell of the outer shell C are respectively formed of a metal sheet by stamping. The rotor A is mounted in the outer shell C and fixedly fastened to respective mounting holes C3 of the outer shell C by tie screws D. The stator B is mounted in the stator A inside the outer shell C with its center shaft extended out of the top and bottom center axle hole C1 of the outer shell C. The matching precision of the rotor A and the stator B is subject to the distance between the central axis of the center axle holes C1 and the periphery C2 of the outer shell C. In order to achieve high precision, the outer diameter A1 and inner diameter A2 of the rotor A must be properly trimmed by means of the application of a CNC (computer numerical control). This processing process takes much time, and greatly increases the manufacturing cost of the ceiling fan motor. Further, because the mounting holes C3 are flat holes directly; cut in the outer shell C, the formation of the mounting holes C3 weakens the structural strength of the outer shell C. When tightening up the tie screws D, the outer shell C may be forced to deform, affecting the precision of the positioning of the rotor A and stator B in the outer shell C. A impact may also causes the outer shell C to deform.
It is one object of the present invention to provide a motor rotor and outer shell mounting structure for ceiling fan, which eliminates the aforesaid drawbacks. According to one aspect of the present invention, the motor rotor and outer shell mounting structure for ceiling fan comprises an outer shell, a stator mounted in the outer shell, and a rotor mounted in the outer shell around the stator for synchronous rotation with the outer shell. The outer shell has inner mounting blocks and outer recessed portions and through holes through the mounting blocks and the recessed portions. The stator has a center shaft extended out of top center axle hole and bottom center axle hole of the outer shell. The rotor has flanged top mounting posts and flanged bottom mounting posts respectively positioned on the mounting blocks and fixedly secured thereto by screws. According to another aspect of the present invention, the flanged top mounting posts and flanged bottom mounting posts each have an axially extended positioning protrusion (flange), and the outer shell has positioning slots adapted to receive the positioning protrusion of each of the flanged top mounting posts and flanged bottom mounting posts for quick positioning of the rotor in the outer shell. According to another aspect of the present invention, the mounting blocks are formed with the recessed portions on the outer shell by stamping, and the formation of the mounting blocks and the recessed portions greatly reinforce the structural strength of the outer shell against deformation.